Today's Smalltalk 4 You starts working with Glorp descriptors - which is how you define mappings between objects and tables in Glorp.. If you have trouble viewing it here in the browser, you can also navigate directly to YouTube. To watch now, click on the image below:

DescriptorSystem defines the basics for interacting with a database using Glorp; the subclass we are setting up will define the table mappings we want to use. Today we are going to define a simple mapping to a table (Emp), and then we are going to use Glorp to create that table in the database. There are a few methods we need to define, all instance side. To start with, we need a #tableForTABLENAMEHERE: method - note the caps, which will be replaced by actual name of the table:

This is the pattern you'll use to map Smalltalk objects (instance variables) to columns. We'll explain how the column names get mapped to instance variables below. You'll also need a method to define all the tables being mapped by this descriptor; it should return an array:

That's how most descriptors you create will look (with the specifics for the tables/classes filled in, of course). Now we can make use of this code to create the Emp table in the database (Oracle in this case):